Configuring The Inverter For Multiple Motors; Simultaneous Connections; Inverter Configuration For Multiple Motor Types - Hitachi L300P Series Instruction Manual

Configuring the Inverter for Multiple Motors

Simultaneous
For some applications, you may need to connect two
Connections or more motors (wired in parallel) to a single
inverter's output. For example, this is common in
conveyor applications where two separate conveyors
need to have approximately the same speed. The use
of two motors may be less expensive than making the
mechanical link for one motor to drive multiple
conveyors.
Some of the requirements when using multiple
motors with one drive are:
• The inverter output must be rated to handle the sum of the currents from the motors.
• You must use separate thermal protection switches or devices to protect each motor. Locate
• The wiring for the motors must be permanently connected in parallel (do not remove one
NOTE: The motor speeds are identical only in theory. That is because slight differences in
their loads will cause one motor to slip a little more than another, even if the motors are identi-
cal. Therefore, do not use this technique for multi-axis machinery that must maintain a fixed
position reference between its axes.
Inverter
Some equipment manufacturers may have a single type of machine that has to support three
different motor types—and only one motor will be connected at a time. For example, an OEM
Configuration for
may sell basically the same machine to the US market and the European market. Some reasons
Multiple Motor
why the OEM needs two motor profiles are:
Types
• The inverter power input voltage is different for these markets.
• The required motor type is also different for each destination.
In other cases, the inverter needs two profiles because the machine characteristics vary accord-
ing to these situations:
• Sometimes the motor load is very light and can move fast. Other times the motor load is
• Sometimes the slower version of the machine does not have special braking options, but a
Having multiple motor profiles lets you store different "personalities" for motors in one
inverter's memory. The inverter allows the final selection between two motor types to be made
in the field through the use of the intelligent input terminal functions [SET]. This provides an
extra level of flexibility needed in particular situations. See the following page.
the device for each motor inside the motor housing or as close to it as possible.
motor from the circuit during operation).
heavy and must move slower. Using two profiles allows the motor speed, acceleration and
deceleration to be optimal for the load and avoid inverter trip (fault) events.
higher performance version does have braking features.
L300P Inverter
U/T1
V/T2
Inverter Motor 1
W/T3
Motor 2
to Nth motor
4–59